This may be of interest to those of you that enjoyed the Timothy Zahn Star Wars novels. This is only spoilery if you watch Star Wars Rebels, but there is a rumor that a certain Admiral will now be included into what Disney considers canon which means that this Admiral is now a player for future movies as well.

British gunners in WWII were able to locate and shoot down German planes at night due to significant advancements in radar technology. To help cover up their improvements on the technology, the British spread about an urban legend that said that they were able to increase the night vision of their pilots by having them consume large amounts of carrots. This propaganda campaign included stories about certain pilots like Lieutenant John "Cat Eyes" Cunningham who they said had exceptional night vision thanks to a habit of eating large amounts of carrots. This lie not only gave birth to an urban legend, but also caused many British people to start planting their own vegetable gardens, including planting and eating a large amount of carrots so that they'd be able to see better during blackouts.

I also had no idea that MI6 used semen as invisible ink which happened to be led at the time by Captain Sir Mansfield Cumming.